Fastest Airplane | Boat | Car
Men of the X-1 |
Secret History |
Sonic Boom |
The Lockheed SR-71 Blackbird is, to date, the fastest airplane ever to streak
across the sky, even though it's more than 30 years old. Capable of speeds
over 2200 miles per hour—that's more than three times the speed of sound—the SR-71 can fly at altitudes above 80,000 feet. What does it feel like to
travel at Mach 3, 15 miles above the earth? Pilots report that, with no
view out the window, there's an eerie sensation of motionlessness when cruising
in the Blackbird.
To fly safely in this harsh, low-pressure environment pilots must wear a
full-pressure suit for protection. Even though the temperature outside the
aircraft hovers around -70 degrees F, the sheer friction of flying at Mach 3
heats the leading edges of the SR-71 to 800 degrees F. To help withstand this
kinetic heat, the Blackbird's airframe is built almost entirely of titanium and
is finished in a special heat-emitting black paint, which helps to cool the
aircraft and gives it its nickname.
The SR-71 can operate for about an hour at top speed before it needs refueling—a feat that can be accomplished in mid-air with a special tanker aircraft.
The Blackbird is powered by two Pratt and Whitney J-58 axial-flow turbojets
with afterburners, each producing about 34,000 pounds of thrust. Studies have
shown that when the aircraft is cruising at Mach 3 or above only about 25 percent of the total thrust is produced by the engines
themselves. The balance is produced by the unique design of the engine inlet
and housing, which is equipped with special afterburners.
The two-seat SR-71 was developed in the early 1960s by the U.S. Air Force as a
strategic reconnaissance aircraft. The first flight of an SR-71 was in 1964 at
a classified location in Nevada. The aircraft's first operational "sortie"
was flown out of Okinawa, Japan in 1968. Most of the SR-71 fleet has now been
retired, except for two Blackbirds currently on loan to NASA's Dryden Flight
Research Center where the aircraft are being used as "test beds" for high
The World Water Speed record, like the air speed record, is decades old.
Australian Ken Warby set the record in 1978 when he averaged 317.60 mph in a
27-foot jet-powered hydroplane called "Spirit of Australia." The official
speed test, which consists of two back-to-back runs over a one-kilometer
straight-away, took place on Blowering Dam in New South Wales, Australia. And where did Warby
design and build this hydraulic masterpiece? Underneath a tree in the back
yard of a house he was renting in suburban Sydney. "There was a canvas sheet I
used to throw over it when it rained," he told the press.
Attempts at beating Warby's record have come at a high price. In 1980, the
previous water speed record holder, Lee Taylor, tried to reclaim his title in a
2.5 million dollar rocket-boat called "Discovery II." The missile-shaped craft
was constructed of aluminum, titanium and stainless steel and was powered by a
rocket engine that burned hydrogen peroxide fuel. On paper, the power plant
generated 8,000 pounds of thrust—or 16,000 horsepower. Taylor believed his
boat would surpass 600 mph.
The trial took place November 13, 1980 on Nevada's Lake Tahoe. Discovery II
roared through its first pass at 269.85 mph and was decelerating when it appeared
to hit a swell. Witnesses reported that the boat veered to the left and
suddenly disintegrated, vanishing under the surface of the lake in a matter of
a few seconds.
Craig Arfons, a former automotive drag racing champion, was the next to take up
the challenge. In 1989, he put the finishing touches on a jet hydroplane
called "Rain-X Record Challenger," which boasted a lightweight composite hull
and a jet engine that could deliver 5,500 horsepower with the afterburner
lit. Arfons calculated that the boat's favorable thrust-to-weight ratio would
give it a 200 percent power advantage over Warby's record-setting boat.
The record attempt took place on Jackson Lake near Sebring, Florida. Members
of Arfons' crew say his boat reached a speed of 263 mph before it became
airborne and began to cartwheel across the mirror-smooth lake. Arfons tried to
deploy a safety parachute, but the angle at which his boat was traveling
prevented the parachute from opening. Arfons was killed as his boat shattered
Recently Warby, now 58, has announced his intention to push his World Water
Speed Record even higher with a new boat currently under construction. "I'm
far too young to be in a rocking chair, so I thought I'd get back in the
The battle to break the sound barrier on land was won exactly 50 years after
Chuck Yeager broke it in the air ... On October 13, 1997, a British jet car
called ThrustSSC made two supersonic passes across Nevada's Black Rock desert
at 760.135 m.p.h. and 763.168 m.p.h. It took British fighter pilot Andy Green
exactly 61 minutes to make the two runs, narrowly disqualifying him for an
official land speed record, which requires that the two runs be made within
60 minutes. Two days later the first ever supersonic World Land Speed Record
was made official when the ThrustSSC completed two runs within an hour at an
average speed of 763.035mph. The British team had been sharing the desert
with another contender, America's Craig Breedlove. His Spirit of America
car had reached a peak speed of 675mph on the Black Rock Desert before
crashing during an October 1996 record attempt. During the October 1997
runs it reached 636mph.
They may not get another chance this year; not only is the weather window
closing, but the desert surface is now occupied by another contender, America's
Craig Breedlove. While both Noble and Breedlove have been relentless in their
pursuit of the sound barrier, their approaches have been wildly different.
Noble has embraced advanced engineering, employing rocket-sled model testing
and computational fluid dynamics in the design of his vehicle. Breedlove, a
race car driver since his teens, has assembled a team of mechanics whose goal,
according to crew chief Dezso Molnar, was to design "a car as simple as we
could possibly make it—with as few moving parts as possible."
Noble's Thrust SSC is the larger and heavier vehicle, measuring 54 feet and
weighing 10 tons. Two Rolls-Royce engines, salvaged from a scrapped Phantom
jet fighter, are anchored to either side of the car's midsection, with the
driver sandwiched between them. Together the engines, which burn jet fuel, have
a combined power of 55,000 pounds of thrust,
or 110,000 horsepower. Breedlove's
Spirit of America is slight by comparison—measuring only 47 feet and
weighing a mere 4 tons. It has one jet engine, a GE J79, that has been
modified to burn regular 92-octane gasoline. Delivering 22,650 pounds of
thrust, the engine is positioned in the rear, while the driver is perched at
the very front of the vehicle. In terms of its thrust-to-weight ratio,
Breedlove's car has a slight advantage over Noble's—2.83-to-1 versus
2.75-to-1, respectively. But clearly power is only part of the equation.
How does one control a vehicle barreling across the desert at speeds over 750
m.p.h.? Noble's Thrust SSC is equipped with two front wheels and a staggered
pair of back wheels, which steer the vehicle. The wheels themselves have no
tires; they are bare disks of forged aluminum. Breedlove's Spirit of America
has three front wheels, set very close together, and two conventionally placed
rear wheels. The front wheels do the steering with the help of a "steering
rudder," which tips the vehicle's fuselage left or right, controlling it like
an airplane. Its tires are made out of a wound carbon composite. For
braking, Thrust uses parachutes as well as disc-style brakes on all four
wheels. Spirit augments its parachutes with a single braking ski that drops
from the cockpit.
The greatest challenge that both cars face is remaining aerodynamically stable
over the course of the run. Going supersonic means passing through a critical
transonic period where air rushes past different parts of the vehicle at
varying speeds, producing pressure and shock waves that influence lift and
drag. Of particular concern is the possibility of becoming airborne—or
digging in to the ground. Neither car is equipped with ejection seats or
Photos: (1-2) Lockheed-Martin Skunk Works; (3) Australian Information Service; (4) Ken
Warby; (5) ThrustSSC; (6) Shell/Spirit of America.
Teacher's Guide |
Editor's Picks |
Previous Sites |
Join Us/E-mail |
About NOVA |
Site Map |
PBS Online |
NOVA Online |
© | Updated October 2000
Support provided by
For new content
visit the redesigned